A safety hasp is a security device having a slotted flap connected at a pin joint to a hinge portion attached by screws to a door or door casement. The slotted part pivots into a "closed" position over the eye ring of a staple attached by screws to the other of the door or door casement. When closed, the flap conceals the screw holes on both the hinge portion and staple plate, so that when a padlock is passed through the eye ring and locked, an intruder cannot unscrew the screws with a screwdriver.
Conventional hasps come in various styles and sizes, with lengths of typically 21/4" to 61/4" and widths of 1" to 2". Though hasps are commonly used on doors, the same also can be used to lock lids of chests and for other types of closures, as well.
It is customary to apply a padlock and hasp, in addition to a factory-installed latch, on the doors of walk-in freezers and similar storage containers in the food service industry. Where hasps are employed on enclosures to limit access to large internal spaces, however, there is a risk that a person will become intentionally or unintentionally locked within the closure. This could occur, for example, where a kitchen employee is inadvertently locked in a meat storage cooler, or where a number of employees are locked into confinement during a robbery.